The Cowboys defense finished third-worst in NFL history last season. They lost DeMarcus Ware, Jason Hatcher and Sean Lee in the off-season.Their starting defensive line has yet to play a game together, with defensive tackle Henry Melton having missed the preseason. Their starting cornerbacks, too, haven’t been on the field together yet, with Morris Claiborne having been out with knee and then shoulder injuries.

They gave up 633 rushing yards and an average of 36 points a game in four preseason games.

Yet, Jerry Jones remains confident that the unit is improved from last season.

“I think the defense is much improved, much improved,” Jones said. “Awareness, the player we’re going to ask to do the job, I think we’re much improved from the team that was on the field the last four games when we ended the season. This is a better defense. We know our limitations. We know our scheme better and we got players that can execute. We’ve got better players, healthier players to execute the scheme. Even the ones who aren’t healthy, including them, we’ve got healthier players that can do it.”